Cake-inhibiting catalyst



Patented Apr. 21, 1942 a No Drawing.

mm SerlalNo. 263.198

Heights, Ohio, assiznors'to The Standard Oil gohmpany, Cleveland, hio,'acorporation oi.

cation March 2r, 1939, I

Is Claims. (cuss-1 23a] m the catalytic treatment of carbon-containingcompoundasuch as alcohols, hydrocarbons,

etc., and particularly hydrocarbons, where the catalyst is=of'oxidetype, a serious practical diiiiculty has the tendency of thecatalyst to coke uni-thereby shortening the possible run, and V addingto the difliculty of regenerating or cleaning, and even afterregeneration has been efiected to the' gr'eatest extent possible, thecatalyst tends to lack a desirablestandard of eiliciency. We

have 1 found however that by providing 1 catalyst compositions of thepeculiar character set forth in detail'belo'mthe surprising resultoccurs that a catalyst does nottend to rapidly coke up such as in thecase-of therknown' oxidecatalysts, and -it regenerates more' readilyand. provides high 'remcieneyas-regenerated.

- T the accomplishment of the foregoing and related ends,- -theinvention, then, comprises the V features-hereinafter fully descrlbed,and particularly pointed out, in the claims, the following descriptionsettingforth in detail certain illustrative embodiments of 'theinvention, these being indicative however, of but a few of the variousways in which the principle of the invention may be employed. v

In accordance with the invention, the catalysts, of oxide character, areprepared such as to contain oxide of copper, this being in minor amountfor the whole composition, and desirably where the catalyst is to beapplied for aromatizing or dehydrogenating hydrocarbons, the othercomponents may be oxides of aluminum and chromium. Whilecopper-containing compositions may be employed in which the proportionsoi the other components vary considerably. it is preferable thataluminum oxide be in the rangeare rather critical. The compositions maybe made by mixing copper oxides with chromium and aluminum oxide; byadsorbing or precipitating copper oxide on the surface of the chromiumand aluminum oxide; or the copper constituent may be co-precipitatedwith the aluminum and chromium constituents by pouring solutionstogether, or better by stage-wise precipitation, in which precipitatingaction is first carried-"on with an insufliciency of the precipitant,and then as a second stage enough precipitant is brought into action tocomplete the precipitation. Gaseous this form of dual'action.'I'he'catalyst is washed free ora'm moniur'n salts by decantation orpreferably by filtration; and is dried'in suitable manner. 'Tliecatalyst may be dried by spreading out a thick layer and passing heatedair over it, after which it may be broken up and screened. A furtherstepof drying at elevated temperature, e. 8. 400 F. or higher, with orwithout avacuum is particularly desirable."

" As illustrativeor' the preparation ofcata- "--lyst,tlie following maybe noted:

'1; 28 partsby-weight-of. an oxide catalyst ma- {terial containing=moi=per centto-20 mm per cent of the oxides of aluminum and chromiumrespectivlm-are moistened with 10,parts-of.asolution containing- 2.43;partsof Cu(NOa) 31-120.

Ammonia gas-isthen applied to precipitate the -copper. The chtalystisthen washed and dried.

II. 425 per ,cent of atheoreticalfprecipitating amount oiammoniumhydroxide is poured into 3,000 partsof-a-solutioncontaining parts ofammonium acetate together withnitrates' of aluminum, chromium andcopperinproportions to furnish 78 mol'per cent A1203, 20 mm per cent CrrOz,and 2 mol per cent CuO. The mixture is allowed to stand about two hours,and it is then filtered and washed by filtration and dried.

IIL By stage-wise precipitation, there is fed to amixing zone 600 partsper minute of a solution containing 960 parts by weight of ammoniumacetate, 6.24 mol aluminum nitrate, 1.6 mol of chromium nitrate, and0.16 mol of copper nitrate per each 48,000 parts of solution, the mixingzone having a capacity of 600 parts of liquid, and

gaseous ammonia is fed in, to '10 per cent neutralization, the over-flowfrom this mixing zone proceedingto another mixing zone in'which thecipitation rate. The catalyst is washed and dried.

In operation for instance in aromatizing hydrocarbons, these catalystsare active at tempera tures of 750-1250 FL, and pressures of atmosphericup to about 400 pounds per square inch.

may be used. Hydfogen or part of the oil-gases recycled may be usedtodilute the fed hydrocarbons, which are supplied in vapor form. Thus, acatalyst of oxides of'copper and aluminum and chromium in proportions of2 mol and 80 mol and 20 mol per cent respectively, operating on naphandaqueous ammonia are especially desirable in 55 tha from Michiganpetroleum, with operating bons, naphthas, and distillates andnon-benzenoid hydrocarbon stocks maybe employed. It is of particularadvantage for instance to fractionally divide a distillate into lightand heavier portions or cuts, and subject these to the action of thecatalyst, and then crack the heavier portion or cut, catalytically orthermally, It is desirable also to treat the product from the catalyticzone by separating aromatics formed, as for instance by a selectivesolvent such as liquid sulphur dioxide or of high boiling amine or aphenol, and

.re-pass theundissolved or non-benzenoid portion into contact with thecatalyst. In general, the feed rates of thehydrocarbon to the catalystmay be 0.1 to 10 gallons per hour per gallon volum of such regenerationmay be employedfor'heating the catalyst bed. It is remarkable that thepresent catalyst is not only regenerated readily, but continues to showlittle coke formation and even less than on the original catalyst.

" Other modes of applying the principle of the invention'may-beemployed, change being made as'regards the details described, providedthe features stated in any of the following'claims. or the equivalent ofsuch, be employed.

1. A process of making a catalyst, which comprises mixing 28 parts byweight of dried coprecipitated aluminum and chromium gel type oxideswith a smaller amount of a solution containing 2.43 parts of coppernitrate, then applying ammonia gas, washing, and drying.

2. A process of making acatalyst, which comrises supplying about 600volumes per minute of a solution containing about 6.24 mol of aluminumnitrate, 1.6 mol of chromium nitrate and 0.16 mol of copper nitrate andan amount of ammonium acetate to a mixing zone and supplying theretogaseous ammonia to about 70 per cent neutralization and flowing thliquid to a further zone in which about 200 volumes per minute of 680parts of concentrated ammonium hydroxide in 16,000 parts of water isfed, passing the liquid through a filter, washing, and drying. 3. Acatalyst consisting of co-precipitated oxides of copper, chromium andaluminum, in

a which the copper oxide is 2-15 mol per cent, the

'We therefore particularly point out and dis- I tinctly claim as ourinvention:

chromium oxide 8.5-49 mol per cent, and the aluminum oxide 42.5-88.2 percent. 7

4. A catalyst consisting of co-precipitated gel type oxides of chromiumand aluminum in the ratio oi 8.5-49 mol per cent of chromium oxide to42.5-88.2 mol per cent aluminum oxide, intimately associated with 2-15mol per cent of copper oxide. 5

5. A catalyst consisting of co-precipitated gel type oxides of copper,chromium and aluminum, in which the copper oxide is 2' mol per cent, thechromium oxide 20 mol per cent, and the aluminum oxide 78 mol per cent.

' '6. A process of making a catalyst which comprises co-precipitatinggel type oxides'ot chromium and aluminum in the ratio of- -49 mol percent of chromium oxide'to 42.5-88.2 mol per cent-aluminum oxide andintimately associating therewith 2-15 mol per cent of copper-oxideROBERT E. BURK. EVERETT C. HUGHES.

-Patent No. $2 0,060.

GERfTI IcATE {0E CORRECTION; 4 April 21, 19M} ROBERT E.-.-BURK, 'ET AL.

It is hereby-certified error ep'pears in the aboiie numberedlpatentrequiring oorrect'ion as follows: In the grent, line-6, and in theheading to mm printedlspeoification, line 2; title of invention, for"CAKE-INHIB- ITING CATALYS T read' -'COKE-INHIBIT I NG CATALYST---andthat the said 1.61:-

ters Patent should be read with this correction therein that the'same'may conform to the record of the case -in the Patent Office.

, Signed and sealed this 16th day of June, A. .D. -19h2.

Ram Van Arsdale,

I (Seal) Acting Commissioner of Patents.

